Fatigue Test Of 6082-T6 Aluminum Alloy And Its Application In Bridge Structure

In recent years,with the rapid development of the municipal transportation industry and the aesthetic requirements of the aesthetic of bridges for urban residents,new-designed aluminum alloy pedestrian bridges have begun to appear in china,and high-strength aluminum alloy of 6082-T6 has been used in bridges.The fatigue performance of aluminum alloy materials under live loads is one of the main concerns.Under the action of alternating loads,the bridge structure may cause fatigue and brittle failure,leading to major engineering accidents.Although most fatigue study was condcucted on steel bridges,concrete bridges and other types of bridges,few studies on the fatigue performance of aluminum alloy materials and bridge structures have been reported.Therefore,research on the fatigue properties of 6082-T6 aluminum alloy materials and structures is important in engineering application value.Based on experiments and finite element results,fatigue performance research on specimens with different stress ratio and different strength was carried out.And then,the fatigue performance of the aluminum alloy hollow slab was studied.The main research contents of this paper are as follows:(1)Static load tests were carried out on 6082-T6 aluminum alloy specimens taken from different cross-section profiles and profiles in different directions to test the physical and mechanical properties of the materials,and provide loading parameters for the corresponding fatigue tests.(2)S-N fatigue test was performed on 6082-T6 aluminum alloy materials commonly used in bridges by using plate samples test.Under a given stress ratio,the difference in the fatigue performance of different profile specimens was found out;And under different stress ratios,the fatigue performance of specimens taken from the same profile was explored under different stress ratio.Using the least square method,test results were to analyze and the S-N curve under the two conditions were decribed.At the same time,the finite element results of the test piece were obtained using ANSYS finite element methed,to compare with tests.(3)Based on the fatigue parameters obtained from the test specimens in Chapter3,the fatigue performance of aluminum alloy hollow panel was studied,and the deterministic S-N curve and Miner model were used to carry out bending fatigue research with different cross-sections.The fatigue limits of two types of hollow panels were compared to determine the better one.The bending fatigue damage and service life of the hollow panel were evaluated and discussed to find out the effect of the fatigue parameters on aluminum alloy hollow panels.Fifty-two figures,forty-seven tables and ninety-five references are in included in the paper.